>>
>>I have a short video where you just see a deaf person say something
>>in sign language.
Rhetorical question: Which sign language?
Practically every country in the world has a different sign language.
Within the United States, there are several used by the deaf (e.g.
American Sign Language vs Pigeon Signed English). Which leads us to...
>Providing captions won't help blind users
Captions probably won't help blind people. But assuming deaf people
wouldn't benefit from closed captions isn't a safe assumption.
Captions could be invaluable to deaf people trying to learn the sign
language being used in the video. For example, there are numerous
deaf people who grew-up using the local spoken language (e.g.
English), but who now wish to learn sign language (e.g. ASL).
-- Terrill --